温度对硅衬底上生长石墨烯的影响

Effects of the Temperature on the Growth of Graphene on Silicon Substrate

通过化学气相沉积(CVD)法在Si衬底上制备石墨烯薄膜,研究了生长温度对薄膜的影响以及石墨烯生长机理。采用傅里叶变换红外光谱(FTIR)、喇曼光谱、光学显微镜(OM)、原子力显微镜(AFM)、扫描电子显微镜(SEM)和X射线光电子谱(XPS)表征石墨烯材料。结果表明,生长温度越高,越有利于Si衬底上石墨烯薄膜的形成和连续。生长过程中,C原子渗入Si衬底表层,在其表面优先形成3C-SiC缓冲层,随后在缓冲层表面重构形成石墨烯。在Si衬底上沉积SiO_2和Si_3N_4覆盖层,发现生长过程中不再出现3C-SiC缓冲层。随着生长温度的增加,石墨烯薄膜缺陷降低,薄膜与衬底之间为范德华力。生长温度1 100℃下结晶质量最好。

Graphene thin films were prepared on Si substrates by chemical vapor deposition（ CVD）method. The influence of the growth temperature on the film and the graphene growth mechanism were studied. The graphene materials were characterized by Fourier transform infrared spectrometer（ FTIR）,Raman spectroscopy,optic microscopy（ OM）, atomic force microscopy（ AFM）, scanning electron microscope（ SEM） and X-ray photoelectron spectroscopy（ XPS）. The results show that the higher of growth temperature,the more benefit for the formation and continuity of the grapheme film on Si substrates. During the growth process,C atoms penetrate into the surface of the Si substrate,and the 3CSi C buffer layer is formed on the surface,then graphene is formed on the surface of the buffer layer.There is no 3C-Si C buffer layer when the Si substrate is covered with Si O2 and Si3N4. With the increase of the growth temperature,the defect of the graphene film decreases,and the graphene film is connected with the composite substrate under Van der Waals force. The crystal quality is the best under the growth temperature of 1 100 ℃.